BY

Richard J. Burley

Dr. James L. Green

Dr. Joseph H. King

Dr. Robert McGuire

Version 1.0 (Draft)

September 14, 1999

________________________________________________________

Dr. James Burch, IMAGE Principal Investigator

________________________________________________________

Richard Burley, IMAGE Ground System Manager

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Dr. James Green, Space Science Data and Operations Office Chief

________________________________________________________

Dr. Joseph King, National Space Science Data Center Head

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Dr. Robert McGuire, Space Physics Data Facility Head

TABLE OF CONTENTS

1. Introduction
1. Purpose and Scope
2. MOU Development, Maintenance, and Management responsibility
2. Mission Overview
1. Science Objectives and Instrumentation
2. Science Data Processing Operations
3. Science Data Products
1. Level-0 Files
2. Level-0.5 Files (UDF)
3. Level-1 Files (CDF)
4. Browse Products (MPEG)
5. Estimated Volume of Science Data Products
4. IMAGE Mission Requirements
1. IMAGE Principal Investigator Requirements
2. IMAGE Science and Mission Operations Center Requirements
3. Code 630/NSSDC/SPDF Requirements
5. References
6. Acronym List

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1.0 INTRODUCTION

This document describes the Memorandum of Understanding (MOU) between the IMAGE Project and the National Space Science Data Center (NSSDC) and the Space Physics Data Facility (SPDF) of the Space Science Data and Operations Office (SSDOO) hereafter collectively called Code 630.

1.1 PURPOSE AND SCOPE

This MOU documents the requirements of the IMAGE Principal Investigator (PI), the IMAGE Ground System Manager (GSM) and IMAGE Mission Operations Manager (MOM) for the Science and Missions Operations Center (SMOC), and Code 630 relating to the production and transfer of IMAGE science data products (SDPs) from the SMOC to Code 630, and the data archiving and distribution services to be provided by Code 630.

1.2 MOU DEVELOPMENT, MAINTAINENCE, AND MANAGEMENT RESPONSIBILITY

The IMAGE Mission Manager (MM) of the IMAGE Project Office at the Goddard Space Flight Center (GSFC), Code 410, is responsible for the development, maintainence, and management of this document until IMAGE has transitioned to nominal operations after launch. After launch and instrument check the responsibility for the IMAGE mission will be transitioned to the Orbiting Satellites Project (OSP, Code 631) within the Space Sciences Directorate. The responsibility for this MOU will also transition to OSP.

2.0 IMAGE MISSION OVERVIEW

The IMAGE mission was selected as a result of AO-95-OSS-02 for MIDEX missions. The Phase B study began on May 10, 1996, and the Mission Confirmation was held on February 25-27, 1997 after which it was confirmed for flight. The IMAGE mission is scheduled to be launched in February 2000.

2.1 SCIENCE OBJECTIVES AND INSTRUMENTATION

The overall science objective of IMAGE is to determine the global response of the magnetosphere to changing conditions in the solar wind. Three fundamental questions which will be addressed by the IMAGE mission are:

IMAGE will address these objectives in unique ways using neutral atom imaging (NAI) over an energy range from 10 eV to 200 keV, far ultraviolet imaging (FUV) from 121 to 190 nm, extreme ultraviolet imaging (EUV) at 30.4 nm, and radio plasma imaging (RPI) over the density range from 0.1 to 105 cm-3 throughout the magnetosphere.

2.2 IMAGE SCIENCE DATA PROCESSING OPERATIONS

2.2.1 OVERVIEW

Because of the fixed MO&DA budget for the mission, the IMAGE Observatory and the Science and Missions Operations Center have been designed to be operated in a ‘lights-out’ mode. The spacecraft will be operated in a ‘store-and-dump’ manner with nominal operations consisting of one short DSN pass per orbit. Some of the data received by the DSN will be forwarded to the SMOC in real time, while the majority of the data will be rate-buffered at the antenna site, and delivered to the SMOC’s Front End Data Server (FEDS) by FTP. The SMOC has the dual goals to; generate and make available IMAGE science data products as rapidly as possible, and to make all of these products using all possible mission data.

2.2.2 QUICKLOOK DATA PROCESSING

To achieve both of these goals, the SMOC will perform two passes through the mission data. The first pass, called the "quicklook" pass, will be executed automatically once the FTP data delivery from the DSN has been completed. The science data products from a quicklook pass will be generated only from the data received in that DSN pass. The quicklook pass shall produce all of the IMAGE science data products, and make them available to the public on the SMOC webserver. These products will not be forwarded to Code 630.

2.2.3 DAILY DATA PROCESSING

The second pass through the data will be initiated by either a member of the Spacecraft Controller Team (SCT) or by chronjob five days to one week (nominally) behind wall-clock time. This extra time will allow for recovery of mission data that may have been lost during a previous DSN pass. This second pass is called a ‘daily’ pass, because it will produce all IMAGE science data products whose data span an entire day. These products will supercede the quicklook products on the SMOC webserver, and will be forwarded to Code 630 for active and permanent archive.

3.0 IMAGE SCIENCE DATA PRODUCTS

The data processing system in the IMAGE Science and Mission Operations Center (SMOC) shall generate all of the IMAGE science data products which are to be received by, and permanently archived by the NSSDC. These products include:

3.1 LEVEL-0 DATA FILES

The SMOC shall process raw IMAGE telemetry into Level-0 telemetry data files by time-ordering all data packets within the file, by eliminating duplicate data packets, and by excluding any data packets determined to have been corrupted during the process of downloading the data from the IMAGE observatory. One Level-0 data file will be produced per instrument per day. All packets within the Level-0 data file that were Rice-Compressed by the IMAGE Central Instrument Data Processor (CIDP) will be decompressed. All data packets within the Level-0 data files shall conform to the CCSDS data standard. The Level-0 data file will be compressed using the standard GZIP program before being FTP’d to Code 630. These files will be named according to the file naming convention adopted by the ISTP program. For example: im_l0_rpi_20001011_v01.lz identifies this file as a level-0 data file for the RPI instrument of the IMAGE mission whose data begins at October 11, 2000 and is the original version of the file.

3.2 LEVEL-0.5 DATA FILES

The SMOC shall execute the software provided by the PI-subcontractor, Chris Gurgiolo, to generate IMAGE data files in the Universal Data Format (UDF) format from Level-0 data files. The UDF format is a multi-file format, with any given data set being defined by four different data files. These four files are Header files, Data Files, Virtual Instrument Definition Files (VIDFs), and Plotting Information Data Files (PIDFs). Multiple UDF data sets will be produced per instrument per day. For more information on the UDF data format see (TBD). In order to simplify the delivery of complete sets of UDF files to users, the SMOC will bundle all types of UDF files and datasets into a single file per instrument per day. These bundles shall be named according to the naming convention required by that system. For example, the bundle named IMAGE.IMAGE-1.UDF.LENA.200010100.tar.gz would include all UDF files for the LENA instrument on the IMAGE-1 spacecraft of the IMAGE project with a data start time of year 2000, day 101, hour 0, bundled with the ‘tar’ utility and Gzipped.

3.3 LEVEL-1 DATA FILES

The SMOC shall generate one Level-1 science data product per instrument per day in Common Data Format (CDF) Version 2.6. These files shall follow the ISTP/IACG standards and conventions. They shall be named according to those same conventions. The SMOC shall also produce attitude and orbit histories in CDF format.

3.4 BROWSE PRODUCT DATA FILES

The SMOC shall also generate a set of science data products in GIF, JPEG and MPEG format for display (i.e. browse) purposes. Since Code 630 has its own set of online display production software (CDAWeb), the SMOC will not send all of the browse products it generates to Code 630. It will send one MPEG movie per day showing the simultaneous observations of all IMAGE instruments at once.

3.5 ESTIMATED VOLUME OF IMAGE SCIENCE DATA PRODUCTS

3.5.1 LEVEL-0 Data Volumes

3.5.2 LEVEL-0.5 (UDF) Data Volumes (since UDF keeps all mission data as counts, it is predicted that the volume of UDF data will be approximately equal to the volume of Level-0 data.

3.5.3 LEVEL-1 (CDF 2.6) Data Volumes

3.5.4 BROWSE PRODUCT (MPEG) Data Volumes

Estimated Mission Total = (122.8G + 122.8G + 128.9G + 6.7G) * 2years = 762 Gbytes

4.1 IMAGE PRINCIPAL INVESTIGATOR REQUIREMENTS

4.1.1
The IMAGE Principal Investigator shall provide Code 630 with a satisfactory set of documentation and software for public use of the IMAGE science data products. This set of documentation and software shall be negotiated by the IMAGE PI and the Code 630 data acquisition scientist.

Response: Accepted

4.2 IMAGE SCIENCE AND MISSIONS OPERATIONS CENTER REQUIREMENTS

4.2.1
The IMAGE SMOC shall deliver all IMAGE data files to Code 630 via FTP to an ingest directory provided by Code 630. The IMAGE SMOC shall not be required to provide any other documentation or files beside the IMAGE data files in order for them to be ingested by Code 630.

Response: Accepted

4.2.2
The IMAGE SMOC shall provide Code 630 with a single copy of any hardcopy media it uses to distribute data to the IMAGE mission scientists. The hardcopy media may be either DVD or CD-ROM.

Response: Accepted

4.2.3
The IMAGE SMOC shall provide Code 630 with definitive and predicted ephemeris data periodically for inclusion onto the Satellite Situation Center system. This ephemeris data shall be given in CDF files. These CDF files shall delivered to the Code 630 IMAGE ingest directory via FTP from the IMAGE SMOC.

Response: Accepted

4.2.4
The IMAGE SMOC shall gzip all level-0 and UDF files in order to make the FTP transfer of the IMAGE science data products more efficient.

Response: Accepted

4.2.5
The IMAGE SMOC shall not be responsible for generating, receiving, or distributing any IMAGE science data products beyond those listed in this document.

Response: Accepted

4.3.1
Code 630 shall provide an acquisition scientist to facilitate and monitor the flow of IMAGE data files from the SMOC and from the IMAGE mission scientists into the archives and data systems of Code 630. The acquisition scientist shall coordinate with the IMAGE PI to accumulate a satisfactory set of documentation about the IMAGE science data products, and any relevant software. The acquisition scientist shall facilitate and monitor all of the services detailed in this MOU.

Response: Accepted

4.3.2
Code 630 shall provide and manage a single ingest directory into which the IMAGE SMOC shall FTP all data files, from the beginning of the mission to the end of IMAGE operations. It is the responsibility of Code 630 to maintain adequate disk space in this directory. It is the responsibility of Code 630 to remove data files from this directory once they have been ingested into their data archive systems.

Response: Accepted

4.3.3
Code 630 shall continue to receive updates to the IMAGE UDF/VIDF, UDF/PIDF, and UDF/SCF from the IMAGE mission scientists once IMAGE mission operations has ended. These updates shall be delivered to the IMAGE acquisition scientist as email attachments.

Response: Accepted

4.3.4
Code 630 shall keep and maintain a log file of all data files that it has moved from its IMAGE ingest directory. Code 630 shall make this log available to IMAGE mission personnel and the IMAGE acquisition scientist upon request.

Response: Accepted

4.3.5
Code 630 shall not require any additional information be deposited into the ingest directory beyond the IMAGE data files themselves. The IMAGE SMOC shall FTP the IMAGE data files, and nothing but the IMAGE data files.

Response: Accepted

4.3.6
Code 630 shall be the active and permanent archive for all of the IMAGE data files.

Response: Accepted

4.3.7
Code 630 shall keep all IMAGE level-zero data files offline for permanent archive.

Response: Accepted

4.3.8
Code 630 shall make all IMAGE UDF data files, all CDF files, and all MPEG files available for electronic download via anonymous FTP on the NDADS and SPYCAT systems or their successors.

Response: Accepted

4.3.9
Code 630 shall make all IMAGE CDF data files available for display and for electronic download on the CDAWeb system or its successors.

Response: Accepted

4.3.10
Code 630 shall make all IMAGE MPEG data files available for display and for electronic download on the TBD system.

Response: Accepted

4.3.11
Code 630 shall receive a single copy of any hardcopy media, which is expected to be DVD or CDROM, used by the IMAGE SMOC to distribute IMAGE data to the IMAGE science team. Code 630 shall keep a library of these disks.

Response: Accepted

4.3.12
Code 630 shall include IMAGE definitive and predicted ephemeris data on the Satellite Situation Center system. The IMAGE SMOC shall provide both definitive and predicted ephemeris periodically in the form of CDF files. The IMAGE SMOC shall deliver these files via FTP into the Code 630 IMAGE ingest directory.

Response: Accepted

4.3.13
Code 630 shall not be responsible for generating, receiving, or distributing any IMAGE science data products beyond those listed in this document, but it may do so at its option.

Response: Accepted

5.0 REFERENCES

6.0 ACRONYM LIST